Context, context, context!! (And a knowledge of Greek Grammar would also help!)
I would suggest you get a copy of Daniel Wallace's book "Greek Grammar Beyond the Basics" before you start spouting off interpretations of Greek syntax and grammar.
"παραδοῦναι τὸν τοιοῦτον τῷ Σατανᾷ εἰς ὄλεθρον τῆς σαρκός, ἵνα τὸ πνεῦμα σωθῇ ἐν τῇ ἡμέρᾳ τοῦ [κυρίου." 1 Cor. 5:5
The word ἵνα (hina) plus the subjunctive has two possible functions in the sentence. One is "purpose" the other is "Purpose-Result." (There is also a very rare third possibility - "consequence not intended.")
However, in many cases, purpose and result cannot be clearly differentiated, hence, ἵνα is used for the result which follows accorded to the purpose of the subject or of God. As in Jewish and pagan thought, purpose and result are identical in declarations of the divine will. The Semitic mind was notoriously unwilling to draw a sharp dividing line between purpose and consequence.
In other words, NT writers employ the language to reflect their theology:
"what God purposes is what happens, consequently, ἵνα is used to express both divine purpose and the result."
Wallace gives the example of John 3:16, which employs ἵνα and two subjunctive verbs follow. "The fact that the subjunctive is all but required after ἵνα does not, of course, argue for uncertainty." John 3:16 unequivocally states that if we believe we ARE saved, even though the verbs are in the subjunctive.
The subjunctive after ἵνα does not necessarily imply any doubt about the fulfillment of the verbal action on the part of the speaker. Further, many instances of purpose clauses shed off into result as well, especially when the divine will is involved. In fact, the verb σωθῇ or sothae, is in the Aorist tense. It is not talking about the probability or possibility of some future event. It is being used to show the divine purpose/result.
So, in context, in English:
"It is actually reported that there is sexual immorality among you, and of a kind that is not tolerated even among pagans, for a man has his father's wife.2 And you are arrogant! Ought you not rather to mourn? Let him who has done this be removed from among you.
For though absent in body, I am present in spirit; and as if present, I have already pronounced judgment on the one who did such a thing.4 When you are assembled in the name of the Lord Jesus and my spirit is present, with the power of our Lord Jesus, 5 you are to deliver this man to Satan for the destruction of the flesh, so that his spirit may be saved in the day of the Lord. 1 Cor. 5:1-5
Paul is talking about a specific circumstance, with a specific purpose and consequence. This is about a man who was committing adultery with his father's wife. The instructions on how to deal with this person are to hand him over to Satan. (Presumably disfellowship him or some sort of physical punishment*??)
If he is thrown out of the congregation, Paul is saying that the purpose/result is that he being saved/delivered/rescued. In fact, God's divine purpose will not be thwarted! In the following passage in a follow up letter, ie 2 Corinthians. we in fact see that the man has in fact repented, and Paul urges the congregation in Corinth to restore him.
"Now if anyone has caused pain, he has caused it not to me, but in some measure—not to put it too severely—to all of you.6 For such a one, this punishment by the majority is enough,7 so you should rather turn to forgive and comfort him, or he may be overwhelmed by excessive sorrow.8 So I beg you to reaffirm your love for him.
9 For this is why I wrote, that I might test you and know whether you are obedient in everything.10 Anyone whom you forgive, I also forgive. Indeed, what I have forgiven, if I have forgiven anything, has been for your sake in the presence of Christ,11 so that we would not be outwitted by Satan; for we are not ignorant of his designs." 2 Cor. 2:5-11
So the purpose of Paul's first admonition was to hand the man over to Satan. God's intention was completely fulfilled, with the result that the man was restored!
What a glorious study in the forgiving grace and the restoration and reconciliation of a believer.
Because the man was saved, but he was committing an egarious sin, it was necessary for some discipline. The discipline, of course, resulted in the divine purpose for the man being fulfilled, and that he was restored to the congregation.
So Paul could not and did not suggest this man was going to hell. Paul did correct his sin, and give some consequences that would have the result of restoration.
You simply cannot pull 1 Cor. 5:5 out of context not only of this chapter but also of 2 Cor. 2 and in fact the entire message of the NT.
The Greek word ἵνα means "that, in order that" and does not imply a condition or possibility that everyone generally "might possibly be saved" if they have sinned. Certainly we can apply the principle to other places where correction is meted out, with the purpose/result that someone who believes can be restored to the congregation when they repent of their sin.
What we cannot do is take one very simple generality "all subjunctives imply only a possibility" when in this case, the subordinate conjunction ἵνα definitely states that the subjunctive verbal "declares God's intention, which is always restoration and reconciliation!"
*Cleon L. Rogers Jr. & Cleon L. Rogers III, The New Linguistic and Exegetical Key to the Greek New Testament. Pg 357
Daniel Wallace, Greek Grammar Beyond the Basis: An Exegetical Syntax of the New Testament. pgs. 471-474
